My PBR Texture looks better in Viewport than in the Render
This is because the material preview render in the viewport automatically uses an environment texture from “C:/Program Files/Blender Foundation/Blender/2.91/datafiles/studiolights/world” as the world background, but by default the rendered world background is solid grey. You can load one of these backgrounds and pipe it into the world’s background color with an Environment Texture node.